PROJECT SUMMARY Collaborative Drug Discovery, Inc. (CDD) proposes to develop a suite of software modules to enable scientists to unambiguously represent chemical mixtures in standard machine-readable formats, filling an urgent and widely-recognized need. Chemicals are typically formulated as mixtures. Recording and communicating information about chemical mixtures is essential for scientists and support staff in the pharmaceutical industry, in academia, in non-profit research organizations, in government, at specialty chemical vendors, and at commercial manufacturers to: ? discover, develop, formulate, manufacture and regulate drugs; ? manage reagent inventories; comply with laboratory safety requirements; inform first responders; ? describe and reproduce biomedical experiments; and ? assess and disseminate information about toxicity risks of chemical reagents and consumer products. A working committee of the International Union of Pure and Applied Chemistry (IUPAC) is close to formalizing ?Mixtures InChI? (or MInChI), which will extend the International Chemical Identifier (InChI) to become the first standard to encompass mixtures. MInChI will effectively index mixtures in the same way that InChI indexes individual compounds. CDD will first develop the data structures and software necessary to enable adoption and utilization of MInChI and create the first general-purpose system for recording information about chemical mixtures that is computable and interoperable. The most innovative part of the project and the bulk of the effort will be to develop a sophisticated automated translation tool that will accurately convert legacy catalogs of chemical mixtures from plaintext descriptions or ad hoc formats so that they are properly represented in a machine readable format that can in turn be easily rendered into MInChI identifiers. The broad vision is to help industry to overcome the barriers to adoption so that MInChI can quickly deliver benefits for drug discovery, chemical safety, and toxicology.